Asked by CBS’s Scott Pelley if Iran could have a nuclear weapon in 2012, Panetta replied: “It would probably be about a year before they could do it. Perhaps a little less. But one proviso, Scott, is that if they have a hidden facility somewhere in Iran that may be enriching fuel.”

Panetta was saying the mullahs are a year or less away from an atom bomb, and if they have a hidden site for enriching uranium to weapons grade, they may be even closer.

“That is a red line for us,” Panetta added. “If we get intelligence they are proceeding with developing a nuclear weapon, then we will take whatever steps necessary to deal with it.”

Panetta is raising the specter of pre-emptive war.

When Pelley’s report hit, however, the Pentagon immediately began to walk the cat back.

“The secretary was clear that we have no indication that the Iranians have made a decision to develop a nuclear weapon,” said Pentagon press secretary George Little. “He (Panetta) didn’t say that Iran would, in fact, have a nuclear weapon in 2012.”

Little added that U.N. inspectors remain in Iran and have access to its uranium stockpile, and should Iran attempt a “breakout” by diverting low-enriched uranium to a hidden facility to convert it to weapons grade, U.N. inspectors would instantly detect the diversion.

“We would retain sufficient time under any such scenario to take appropriate action,” said Little.

In short, the Pentagon does not believe Iran has made a decision to build atomic weapons, and the department is confident that, should it do so, the United States would have ample warning.

Little’s definitive statement, “We have no indication that the Iranians have made a decision to develop a nuclear weapon,” coincides with the consensus of all 16 U.S. intelligence agencies, including the CIA and Defense Intelligence Agency, in December 2007.

In that report, the entire U.S. intelligence community stated unanimously, with “high confidence,” that Iran had given up its drive for an atom bomb back in 2003.

Yet the Pentagon‘s categorical statement this week, and the 2007 declaration by the entire U.S. intelligence community that Iran abandoned its bomb program in 2003, raises a question.

How could the International Atomic Energy Agency conclude, as it did last month, that Iran “has carried out activities relevant to the development of a nuclear device”? Did the IAEA discover clandestine bomb-building that our own intelligence community failed to detect?

If Iran is doing experiments consistent with building an atomic bomb, as the IAEA reports, why does the U.S. intelligence community not revise and update its 2007 report? Why are CIA and DIA silent?

This is no minor matter. For not only have Panetta and Barack Obama talked about “all options on the table” regarding Iran — i.e., we do not rule out military strikes — so, too, have the GOP presidential candidates, save Rep. Ron Paul.

Sen. Rick Santorum says we are already at war:

“Iran is a country that has been at war with us since 1979. … The Iranians are the existential threat to Israel.”

In fierce rebuttal to Paul’s suggestion that the real threat to America is being stampeded into a new war, Rep. Michele Bachmann retorted:

“We know beyond the shadow of a doubt that Iran will take a nuclear weapon, they will use it to wipe our ally Israel off the face of the map. … The Iran Constitution … states unequivocally that their mission is to extend jihad across the world and eventually to set up a worldwide caliphate.”

But is all this consistent or credible?

If Iran is an “existential threat” to Israel and intends to use a bomb it is now building on Israel, why have the Israelis, with 200 to 300 nuclear weapons, who have bombed both Iraqi and Syrian nuclear sites, not removed that “existential threat” themselves?

Second, assume the Bachmann horror scenario that we know “beyond the shadow of a doubt” that Iran, as soon as it gets the bomb it is building, will use it on Israel. If that is so, who does Bachmann think will then be establishing that caliphate in an Iran that an Israeli retaliatory strike will have reduced to atomic ash?

Lest we forget, the Israelis are a “Never Again!” nation.

And there is another serious matter here. While Obamaites, neocons and Republicans are talking about “all options on the table,” the war option, if we still have a Constitution, cannot be used against a nation that has not attacked us, unless Congress, which alone has the power to declare war, has authorized military action.